Fragrance allergens › Vanillin
Vanillin (CAS 121-33-5) is one of the fragrance allergens the European Union requires to be named on a label once it passes a threshold. It is rarely something you added on purpose: 59 materials in this catalog carry it as a constituent, which is how a formula ends up over the line without a single line item admitting to it.
Contents are estimates from typical published compositions, not a certificate of analysis for your bottle. A supplier's own figures always win.
PerfuMate totals these across a whole formula while you compose, counting the same molecule arriving from several materials at once, and writes the declaration for the back of the bottle. Open the bench, free and without an account.